include/net/sch_generic.h

   1 #ifndef __NET_SCHED_GENERIC_H
   2 #define __NET_SCHED_GENERIC_H
   3
   4 #include <linux/netdevice.h>
   5 #include <linux/types.h>
   6 #include <linux/rcupdate.h>
   7 #include <linux/module.h>
   8 #include <linux/pkt_sched.h>
   9 #include <linux/pkt_cls.h>
  10 #include <net/gen_stats.h>
  11 #include <net/rtnetlink.h>
  12
  13 struct Qdisc_ops;
  14 struct qdisc_walker;
  15 struct tcf_walker;
  16 struct module;
  17
  18 struct qdisc_rate_table {
  19         struct tc_ratespec rate;
  20         u32             data[256];
  21         struct qdisc_rate_table *next;
  22         int             refcnt;
  23 };
  24
  25 enum qdisc_state_t {
  26         __QDISC_STATE_RUNNING,
  27         __QDISC_STATE_SCHED,
  28         __QDISC_STATE_DEACTIVATED,
  29 };
  30
  31 struct qdisc_size_table {
  32         struct list_head        list;
  33         struct tc_sizespec      szopts;
  34         int                     refcnt;
  35         u16                     data[];
  36 };
  37
  38 struct Qdisc {
  39         int                     (*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
  40         struct sk_buff *        (*dequeue)(struct Qdisc *dev);
  41         unsigned                flags;
  42 #define TCQ_F_BUILTIN           1
  43 #define TCQ_F_THROTTLED         2
  44 #define TCQ_F_INGRESS           4
  45 #define TCQ_F_CAN_BYPASS        8
  46 #define TCQ_F_MQROOT            16
  47 #define TCQ_F_WARN_NONWC        (1 << 16)
  48         int                     padded;
  49         struct Qdisc_ops        *ops;
  50         struct qdisc_size_table *stab;
  51         struct list_head        list;
  52         u32                     handle;
  53         u32                     parent;
  54         atomic_t                refcnt;
  55         struct gnet_stats_rate_est      rate_est;
  56         int                     (*reshape_fail)(struct sk_buff *skb,
  57                                         struct Qdisc *q);
  58
  59         void                    *u32_node;
  60
  61         /* This field is deprecated, but it is still used by CBQ
  62          * and it will live until better solution will be invented.
  63          */
  64         struct Qdisc            *__parent;
  65         struct netdev_queue     *dev_queue;
  66         struct Qdisc            *next_sched;
  67
  68         struct sk_buff          *gso_skb;
  69         /*
  70          * For performance sake on SMP, we put highly modified fields at the end
  71          */
  72         unsigned long           state;
  73         struct sk_buff_head     q;
  74         struct gnet_stats_basic_packed bstats;
  75         struct gnet_stats_queue qstats;
  76 };
  77
  78 struct Qdisc_class_ops {
  79         /* Child qdisc manipulation */
  80         struct netdev_queue *   (*select_queue)(struct Qdisc *, struct tcmsg *);
  81         int                     (*graft)(struct Qdisc *, unsigned long cl,
  82                                         struct Qdisc *, struct Qdisc **);
  83         struct Qdisc *          (*leaf)(struct Qdisc *, unsigned long cl);
  84         void                    (*qlen_notify)(struct Qdisc *, unsigned long);
  85
  86         /* Class manipulation routines */
  87         unsigned long           (*get)(struct Qdisc *, u32 classid);
  88         void                    (*put)(struct Qdisc *, unsigned long);
  89         int                     (*change)(struct Qdisc *, u32, u32,
  90                                         struct nlattr **, unsigned long *);
  91         int                     (*delete)(struct Qdisc *, unsigned long);
  92         void                    (*walk)(struct Qdisc *, struct qdisc_walker * arg);
  93
  94         /* Filter manipulation */
  95         struct tcf_proto **     (*tcf_chain)(struct Qdisc *, unsigned long);
  96         unsigned long           (*bind_tcf)(struct Qdisc *, unsigned long,
  97                                         u32 classid);
  98         void                    (*unbind_tcf)(struct Qdisc *, unsigned long);
  99
 100         /* rtnetlink specific */
 101         int                     (*dump)(struct Qdisc *, unsigned long,
 102                                         struct sk_buff *skb, struct tcmsg*);
 103         int                     (*dump_stats)(struct Qdisc *, unsigned long,
 104                                         struct gnet_dump *);
 105 };
 106
 107 struct Qdisc_ops {
 108         struct Qdisc_ops        *next;
 109         const struct Qdisc_class_ops    *cl_ops;
 110         char                    id[IFNAMSIZ];
 111         int                     priv_size;
 112
 113         int                     (*enqueue)(struct sk_buff *, struct Qdisc *);
 114         struct sk_buff *        (*dequeue)(struct Qdisc *);
 115         struct sk_buff *        (*peek)(struct Qdisc *);
 116         unsigned int            (*drop)(struct Qdisc *);
 117
 118         int                     (*init)(struct Qdisc *, struct nlattr *arg);
 119         void                    (*reset)(struct Qdisc *);
 120         void                    (*destroy)(struct Qdisc *);
 121         int                     (*change)(struct Qdisc *, struct nlattr *arg);
 122         void                    (*attach)(struct Qdisc *);
 123
 124         int                     (*dump)(struct Qdisc *, struct sk_buff *);
 125         int                     (*dump_stats)(struct Qdisc *, struct gnet_dump *);
 126
 127         struct module           *owner;
 128 };
 129
 130
 131 struct tcf_result {
 132         unsigned long   class;
 133         u32             classid;
 134 };
 135
 136 struct tcf_proto_ops {
 137         struct tcf_proto_ops    *next;
 138         char                    kind[IFNAMSIZ];
 139
 140         int                     (*classify)(struct sk_buff*, struct tcf_proto*,
 141                                         struct tcf_result *);
 142         int                     (*init)(struct tcf_proto*);
 143         void                    (*destroy)(struct tcf_proto*);
 144
 145         unsigned long           (*get)(struct tcf_proto*, u32 handle);
 146         void                    (*put)(struct tcf_proto*, unsigned long);
 147         int                     (*change)(struct tcf_proto*, unsigned long,
 148                                         u32 handle, struct nlattr **,
 149                                         unsigned long *);
 150         int                     (*delete)(struct tcf_proto*, unsigned long);
 151         void                    (*walk)(struct tcf_proto*, struct tcf_walker *arg);
 152
 153         /* rtnetlink specific */
 154         int                     (*dump)(struct tcf_proto*, unsigned long,
 155                                         struct sk_buff *skb, struct tcmsg*);
 156
 157         struct module           *owner;
 158 };
 159
 160 struct tcf_proto {
 161         /* Fast access part */
 162         struct tcf_proto        *next;
 163         void                    *root;
 164         int                     (*classify)(struct sk_buff*, struct tcf_proto*,
 165                                         struct tcf_result *);
 166         __be16                  protocol;
 167
 168         /* All the rest */
 169         u32                     prio;
 170         u32                     classid;
 171         struct Qdisc            *q;
 172         void                    *data;
 173         struct tcf_proto_ops    *ops;
 174 };
 175
 176 struct qdisc_skb_cb {
 177         unsigned int            pkt_len;
 178         char                    data[];
 179 };
 180
 181 static inline int qdisc_qlen(struct Qdisc *q)
 182 {
 183         return q->q.qlen;
 184 }
 185
 186 static inline struct qdisc_skb_cb *qdisc_skb_cb(struct sk_buff *skb)
 187 {
 188         return (struct qdisc_skb_cb *)skb->cb;
 189 }
 190
 191 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
 192 {
 193         return &qdisc->q.lock;
 194 }
 195
 196 static inline struct Qdisc *qdisc_root(struct Qdisc *qdisc)
 197 {
 198         return qdisc->dev_queue->qdisc;
 199 }
 200
 201 static inline struct Qdisc *qdisc_root_sleeping(struct Qdisc *qdisc)
 202 {
 203         return qdisc->dev_queue->qdisc_sleeping;
 204 }
 205
 206 /* The qdisc root lock is a mechanism by which to top level
 207  * of a qdisc tree can be locked from any qdisc node in the
 208  * forest.  This allows changing the configuration of some
 209  * aspect of the qdisc tree while blocking out asynchronous
 210  * qdisc access in the packet processing paths.
 211  *
 212  * It is only legal to do this when the root will not change
 213  * on us.  Otherwise we'll potentially lock the wrong qdisc
 214  * root.  This is enforced by holding the RTNL semaphore, which
 215  * all users of this lock accessor must do.
 216  */
 217 static inline spinlock_t *qdisc_root_lock(struct Qdisc *qdisc)
 218 {
 219         struct Qdisc *root = qdisc_root(qdisc);
 220
 221         ASSERT_RTNL();
 222         return qdisc_lock(root);
 223 }
 224
 225 static inline spinlock_t *qdisc_root_sleeping_lock(struct Qdisc *qdisc)
 226 {
 227         struct Qdisc *root = qdisc_root_sleeping(qdisc);
 228
 229         ASSERT_RTNL();
 230         return qdisc_lock(root);
 231 }
 232
 233 static inline struct net_device *qdisc_dev(struct Qdisc *qdisc)
 234 {
 235         return qdisc->dev_queue->dev;
 236 }
 237
 238 static inline void sch_tree_lock(struct Qdisc *q)
 239 {
 240         spin_lock_bh(qdisc_root_sleeping_lock(q));
 241 }
 242
 243 static inline void sch_tree_unlock(struct Qdisc *q)
 244 {
 245         spin_unlock_bh(qdisc_root_sleeping_lock(q));
 246 }
 247
 248 #define tcf_tree_lock(tp)       sch_tree_lock((tp)->q)
 249 #define tcf_tree_unlock(tp)     sch_tree_unlock((tp)->q)
 250
 251 extern struct Qdisc noop_qdisc;
 252 extern struct Qdisc_ops noop_qdisc_ops;
 253 extern struct Qdisc_ops pfifo_fast_ops;
 254 extern struct Qdisc_ops mq_qdisc_ops;
 255
 256 struct Qdisc_class_common {
 257         u32                     classid;
 258         struct hlist_node       hnode;
 259 };
 260
 261 struct Qdisc_class_hash {
 262         struct hlist_head       *hash;
 263         unsigned int            hashsize;
 264         unsigned int            hashmask;
 265         unsigned int            hashelems;
 266 };
 267
 268 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
 269 {
 270         id ^= id >> 8;
 271         id ^= id >> 4;
 272         return id & mask;
 273 }
 274
 275 static inline struct Qdisc_class_common *
 276 qdisc_class_find(struct Qdisc_class_hash *hash, u32 id)
 277 {
 278         struct Qdisc_class_common *cl;
 279         struct hlist_node *n;
 280         unsigned int h;
 281
 282         h = qdisc_class_hash(id, hash->hashmask);
 283         hlist_for_each_entry(cl, n, &hash->hash[h], hnode) {
 284                 if (cl->classid == id)
 285                         return cl;
 286         }
 287         return NULL;
 288 }
 289
 290 extern int qdisc_class_hash_init(struct Qdisc_class_hash *);
 291 extern void qdisc_class_hash_insert(struct Qdisc_class_hash *, struct Qdisc_class_common *);
 292 extern void qdisc_class_hash_remove(struct Qdisc_class_hash *, struct Qdisc_class_common *);
 293 extern void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
 294 extern void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
 295
 296 extern void dev_init_scheduler(struct net_device *dev);
 297 extern void dev_shutdown(struct net_device *dev);
 298 extern void dev_activate(struct net_device *dev);
 299 extern void dev_deactivate(struct net_device *dev);
 300 extern struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
 301                                      struct Qdisc *qdisc);
 302 extern void qdisc_reset(struct Qdisc *qdisc);
 303 extern void qdisc_destroy(struct Qdisc *qdisc);
 304 extern void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
 305 extern struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 306                                  struct Qdisc_ops *ops);
 307 extern struct Qdisc *qdisc_create_dflt(struct net_device *dev,
 308                                        struct netdev_queue *dev_queue,
 309                                        struct Qdisc_ops *ops, u32 parentid);
 310 extern void qdisc_calculate_pkt_len(struct sk_buff *skb,
 311                                    struct qdisc_size_table *stab);
 312 extern void tcf_destroy(struct tcf_proto *tp);
 313 extern void tcf_destroy_chain(struct tcf_proto **fl);
 314
 315 /* Reset all TX qdiscs of a device.  */
 316 static inline void qdisc_reset_all_tx(struct net_device *dev)
 317 {
 318         unsigned int i;
 319         for (i = 0; i < dev->num_tx_queues; i++)
 320                 qdisc_reset(netdev_get_tx_queue(dev, i)->qdisc);
 321 }
 322
 323 /* Are all TX queues of the device empty?  */
 324 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
 325 {
 326         unsigned int i;
 327         for (i = 0; i < dev->num_tx_queues; i++) {
 328                 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
 329                 const struct Qdisc *q = txq->qdisc;
 330
 331                 if (q->q.qlen)
 332                         return false;
 333         }
 334         return true;
 335 }
 336
 337 /* Are any of the TX qdiscs changing?  */
 338 static inline bool qdisc_tx_changing(struct net_device *dev)
 339 {
 340         unsigned int i;
 341         for (i = 0; i < dev->num_tx_queues; i++) {
 342                 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
 343                 if (txq->qdisc != txq->qdisc_sleeping)
 344                         return true;
 345         }
 346         return false;
 347 }
 348
 349 /* Is the device using the noop qdisc on all queues?  */
 350 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
 351 {
 352         unsigned int i;
 353         for (i = 0; i < dev->num_tx_queues; i++) {
 354                 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
 355                 if (txq->qdisc != &noop_qdisc)
 356                         return false;
 357         }
 358         return true;
 359 }
 360
 361 static inline unsigned int qdisc_pkt_len(struct sk_buff *skb)
 362 {
 363         return qdisc_skb_cb(skb)->pkt_len;
 364 }
 365
 366 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
 367 enum net_xmit_qdisc_t {
 368         __NET_XMIT_STOLEN = 0x00010000,
 369         __NET_XMIT_BYPASS = 0x00020000,
 370 };
 371
 372 #ifdef CONFIG_NET_CLS_ACT
 373 #define net_xmit_drop_count(e)  ((e) & __NET_XMIT_STOLEN ? 0 : 1)
 374 #else
 375 #define net_xmit_drop_count(e)  (1)
 376 #endif
 377
 378 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 379 {
 380 #ifdef CONFIG_NET_SCHED
 381         if (sch->stab)
 382                 qdisc_calculate_pkt_len(skb, sch->stab);
 383 #endif
 384         return sch->enqueue(skb, sch);
 385 }
 386
 387 static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
 388 {
 389         qdisc_skb_cb(skb)->pkt_len = skb->len;
 390         return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
 391 }
 392
 393 static inline void __qdisc_update_bstats(struct Qdisc *sch, unsigned int len)
 394 {
 395         sch->bstats.bytes += len;
 396         sch->bstats.packets++;
 397 }
 398
 399 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
 400                                        struct sk_buff_head *list)
 401 {
 402         __skb_queue_tail(list, skb);
 403         sch->qstats.backlog += qdisc_pkt_len(skb);
 404         __qdisc_update_bstats(sch, qdisc_pkt_len(skb));
 405
 406         return NET_XMIT_SUCCESS;
 407 }
 408
 409 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
 410 {
 411         return __qdisc_enqueue_tail(skb, sch, &sch->q);
 412 }
 413
 414 static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch,
 415                                                    struct sk_buff_head *list)
 416 {
 417         struct sk_buff *skb = __skb_dequeue(list);
 418
 419         if (likely(skb != NULL))
 420                 sch->qstats.backlog -= qdisc_pkt_len(skb);
 421
 422         return skb;
 423 }
 424
 425 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
 426 {
 427         return __qdisc_dequeue_head(sch, &sch->q);
 428 }
 429
 430 static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
 431                                                    struct sk_buff_head *list)
 432 {
 433         struct sk_buff *skb = __skb_dequeue_tail(list);
 434
 435         if (likely(skb != NULL))
 436                 sch->qstats.backlog -= qdisc_pkt_len(skb);
 437
 438         return skb;
 439 }
 440
 441 static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
 442 {
 443         return __qdisc_dequeue_tail(sch, &sch->q);
 444 }
 445
 446 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
 447 {
 448         return skb_peek(&sch->q);
 449 }
 450
 451 /* generic pseudo peek method for non-work-conserving qdisc */
 452 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
 453 {
 454         /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
 455         if (!sch->gso_skb) {
 456                 sch->gso_skb = sch->dequeue(sch);
 457                 if (sch->gso_skb)
 458                         /* it's still part of the queue */
 459                         sch->q.qlen++;
 460         }
 461
 462         return sch->gso_skb;
 463 }
 464
 465 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
 466 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
 467 {
 468         struct sk_buff *skb = sch->gso_skb;
 469
 470         if (skb) {
 471                 sch->gso_skb = NULL;
 472                 sch->q.qlen--;
 473         } else {
 474                 skb = sch->dequeue(sch);
 475         }
 476
 477         return skb;
 478 }
 479
 480 static inline void __qdisc_reset_queue(struct Qdisc *sch,
 481                                        struct sk_buff_head *list)
 482 {
 483         /*
 484          * We do not know the backlog in bytes of this list, it
 485          * is up to the caller to correct it
 486          */
 487         __skb_queue_purge(list);
 488 }
 489
 490 static inline void qdisc_reset_queue(struct Qdisc *sch)
 491 {
 492         __qdisc_reset_queue(sch, &sch->q);
 493         sch->qstats.backlog = 0;
 494 }
 495
 496 static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
 497                                               struct sk_buff_head *list)
 498 {
 499         struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);
 500
 501         if (likely(skb != NULL)) {
 502                 unsigned int len = qdisc_pkt_len(skb);
 503                 kfree_skb(skb);
 504                 return len;
 505         }
 506
 507         return 0;
 508 }
 509
 510 static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
 511 {
 512         return __qdisc_queue_drop(sch, &sch->q);
 513 }
 514
 515 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
 516 {
 517         kfree_skb(skb);
 518         sch->qstats.drops++;
 519
 520         return NET_XMIT_DROP;
 521 }
 522
 523 static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
 524 {
 525         sch->qstats.drops++;
 526
 527 #ifdef CONFIG_NET_CLS_ACT
 528         if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
 529                 goto drop;
 530
 531         return NET_XMIT_SUCCESS;
 532
 533 drop:
 534 #endif
 535         kfree_skb(skb);
 536         return NET_XMIT_DROP;
 537 }
 538
 539 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
 540    long it will take to send a packet given its size.
 541  */
 542 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
 543 {
 544         int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
 545         if (slot < 0)
 546                 slot = 0;
 547         slot >>= rtab->rate.cell_log;
 548         if (slot > 255)
 549                 return (rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF]);
 550         return rtab->data[slot];
 551 }
 552
 553 #ifdef CONFIG_NET_CLS_ACT
 554 static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask)
 555 {
 556         struct sk_buff *n = skb_clone(skb, gfp_mask);
 557
 558         if (n) {
 559                 n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
 560                 n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
 561                 n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
 562         }
 563         return n;
 564 }
 565 #endif
 566
 567 #endif